Incorrect. What you're talking about is switching graphic cards with a hardware mux. But Optimus is *not* about switching, never was. Pure Optimus laptops do not have a hardware mux, and this isn't new with the Ivy Bridge + 675M combo as you claim it is. Some laptops do have a mux and a BIOS option for "integrated/dedicated/Optimus". But that's a feature they provide in addition to Optimus. The point of Optimus is to operate without a mux.

Quote:

Originally Posted by NVidia

Like a Hybrid car seamlessly transitions from gas to electric, NVIDIA Optimus technology automatically optimizes your computing experience so you can keep working without interruptions.

I may be wrong, but I'm going by what NVidia describes in layman's terms. I'm a software guy, so I never bothered to understand what is happening in depth with Optimus mainly because I didn't care. I want a desktop replacement laptop, a couple of hours of battery life is all I want.

I've never heard of Nvidia GPUs not working at all under Linux until now. I'm currently using a 420M with no problems. Just because I haven't heard of it doesn't mean it's not true, but I believe it is far less common. With the introduction of the Ivy Bridge + 675m combination it may end up being far more common.

Quote:

Originally Posted by Gusar

It's not on Nvidia alone to make Optimus happen. They need DMA-BUF. Texas Instruments, one of the major players in creating DMA-BUF, agrees that Nvidia should be able to have it. The rules of the Linux kernel, as quoted by the the Nvidia dev, agree that they should be able to have it. It's all here: https://lkml.org/lkml/2012/2/19/88

I do agree with the fact that is a combination of Nvidia and the Kernel devs. As I stated previously it looks to be the common disagreements with the Kernel devs and proprietary players. In the end it's hurting us. I will appropriately switch some of my blame on the kernel devs as well if it makes you feel better.